Torque wrench



Sept. 24, 1946. I D. s. OLIVER ETA-L 3 TOR UE WRENCH Filed may 21, 1943.

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Patented S ept. 24 1946 g UNITED STATES "PATENT oFncE Delbert s; Oliver, Euclid, and John Kanuch, Cleveland,.0hio, assignors to Pesco Products 00., a corporation of Ohio Application May'Zl. 1943, Serial No. 487,896

This invention relates. to improvements in wrenches for securely gripping rounded objects, such, for example, as stud bolts, for applying turning torque thereto in either direction.

It is a general object of this invention to provide an improved arrangement of mechanism forming a gripping wrench of the overrunning clutch type, particularly adapted for .engaging the unthreaded portion of a cylindrical object such as a stud bolt for applying turning torque thereto in either direction, which arrangement is both relatively 'simpleof construction and inexpensive of manufacture while at the same time being emcient in operation and maintenance.

It is a further object to provide an improved torque wrench arrangement, the principal parts of which may readily be fabricated from commonly available bar stock by simple turning and machining operations.

A further object is to provide in awrench assembly, including a housing having therein an arcuately adjustable cage and cam operated overrunning rollers, means for readily indicating the arcuate positions of the cage together with readily engageable manual means for predetermining the position of arcuate adjustment of the cage relative to the housing.

Other and more particular objects,jadvantages and uses of the invention will become apparent from a reading of the following specification taken in connection with the appended drawing forming a part thereof and wherein:

Fig. l is an axial cross-section view of a wrench assembly in accordance with a preferred embodiment of the invention and showing the stud in position therein with the gripping rollers in neu-. tral position;

Fig. 2 is a cross-section view taken substantially on the line 2-2 of Fig. 1 and showing to advantage the relationship of detent means and manual means for adjusting the arcuate position of the cage;

Fig. 3 is a cross-section view taken substantially on the line 3-3 of Fig. 1 and showing to advantage the arrangement of gripping rollers and cam surfaces cooperating therewith for effooting the gripping action;

Fig. 4 is an elevation view of the cage and rollerassembly shown removed from the housing; and

Fig. 5 is a cross-section view corresponding to Fig. 3 but showing the cage and roller assembly in the arcuate position wherein the relatively large roller has been moved into engagement with one of the cam surfaces and a stud has been gripped between the three rollers.

Referring in greater detail to the figures of the drawing, a preferred embodiment of the invention is shown as comprising a wrench assembly l0 including a main housing I2 incorporating a gripping assembly M adapted to engage and apply torque in either direction to a smooth circular object such as a stud IS, the housing J2 being provided with radially extending, manually engageable handles 18 for applying torque.

The housing l2 may be readily formed from a piece of commonly available cylindrical bar stock by machining therein a coaxial bore vZll capable of receiving one of the terminals of .a stud in guided relation thereto but with a liberal clearance, with bore 20 being enlarged at the working end to provide a cylindrical cage-receiving bore 22. In addition, this enlarged bore 22 is further recessed along a portion only of its axial extent to define'a pair of opposed cam surfaces 24 and 25 separated by a. relatively short dwell surface 28.

Cage assembly M comprises a tubular cage defining member 30 formed in the lower terminal portion thereof with a plurality of radially extending recesses 32 separated by axially extending barlike portions 34, these radial recesses 32 functioning as cages for the reception of cylindrical rollers 36, 38 and It will be noted that roller 38 is larger than rollers 36 and 4t], roller 38 being the working roller cooperating with opposed cam surfaces ZG-or 26 depending upon the direction of operation of the tool and effective to apply a radial inward force against the embraced stud I6 for holding the same against smaller rollers 36 and 40 for gripping the stud against turning relative to the tool when the tool handles 18 are turned. The relative size of roller 38 to that of rollers 33 and 46 is such that with a stud H5 in position between the three rollers and the rollers 36 and 40 in engagement with the circular. wall portion 22.0-f the bore and the larger roller 38 in engagement with the dwell portion 28 the clearance between the periphery of the stud and the respective rollers will be substantially the same -with the stud positioned axially in substantial alignment with bore 28 of the housing. Tubular cage M requires only a simple machining operation to provide a proper journalled relation within large bore 22 and to provide the radially extending slots 32, defining the cage or rollerreceiving chambers.

Cage assembly I4 is retained withinenlarged bore 22 by means of a sheet metal retainer 42 centrally orificed for the passage of the stud and formed on the peripheral portion thereof with an I) inturned flange 44 for cooperation with a complementarily formed recess in housing l2 effective to prevent inadvertent removal.

For the very important purpose of adjusting the cage assembly 14 to the neutral or mid-position thereof and furnishin a definite indication of the position of the cage assembly, there is provided a detent arrangement and a manually engageable handle for arcuately adjusting the cage. The detent arrangement comprises radially extending bore 46 adapted to receive a ball 48 of slightly larger diameter in cooperation with the inner terminal thereof, which ball in turn is mounted in a radially extending bore 50 formed in tubular cage 30, this ball being normally urged radially outwardly by coil compression spring 5i. Thus when cage assembly 14 is located in the neutral or mid-position thereof with the relatively large, Work-performing 'roller 38 in contact with dwell surface 28, the index ball 48 engages the inner terminal of bore 4'6 giving a definite indication of its position on the cage assembly as well as resiliently retaining the same in such position.

For the very important purpose of arcuately adjusting cage assembly as, there is provided a manually engageable handle 52 in the form of a radially extending pin inserted into the wall of tubular cage 38. The handle 52 protrudes through a slot 54 of an arcuate extent such as to properly correlatethe limits of arcuate adjustment of cage assembly M with the rises 24 and 26 of the cam to effect the proper gripping of the stud by the rollers.

It will thus be seen that when it is desired to employ the stud wrench, manual adjusting handle 52 is moved arcuately to the mid-position of slot 54 thus adjusting large working roller 38 to its mid-position in cooperation with the dwell surface 23 and affording the maximum opening between the rollers for the introduction of stud it all as indicated in Fig. l. The ball 48 is effective to resiliently maintain this neutral or mid-position of the cage and roller assembly. When the tool has been placed about a stud, manual adjusting handle 52 is moved arcuately to one side or the other depending upon whether a stud is to be screwed more tightly into position or to be removed from its mounting, to thus cause large working roller 38 to move into engagement with either cam surface 2 3 or cam surface 26, as the case may be, and hence accomplish locking engagement of the stud between the three rollers. With the stud thus locked in position the handles l8 maybe employed to apply the requisite torque to the tool housing [2 and hence effect the turning of the stud l8.

' While we have disclosed our invention in connection with a specific embodiment thereof, this is intended by way of example only, our invention being defined by the appended claims.

We claim:

1. In a torque wrench particularly adapted for drivingly engaging the smooth intermediate periphery of a terminally threaded stud, including means-defining a cylindrical housing having a coaxially extending bore therein adapted to receive a stud with one terminal portion thereof protruding from said bore, means defining a cage and cylindrical roller assembly receivable in said bore in journalled arcuately adjustable relation thereto, said cage including a tubular portion for journalled engagement with said bore and formed with a plurality of radially extending recesses in the wall thereof separated by axially extending circumferentially spaced cage-defining bars, a re- 4 cessed cam-defining surface in the inner periphery of said housing bore in the area opposite one pair of said bars, said recess cam-defining surface including a centrally disposed dwell surface, a pair of oppositely extending rises or cam surfaces, a cylindrical roller received :between said bars in opposed relation to said cam defining recess, a plurality of additional cylindrical rollers received within the remainin recesses and spaced apart by said bars for cooperation with the circular portion of said bore, said first-named roller being larger than said remaining rollers by an amount such that when said large roller is in engagement with said dwell surface of said recess and said remaining rollers are in engagement with the circular portion of said bore with a stud positioned axially within said rollers the clearance between the periphery of the stud and the respective rollers is substantially the same, means defining a detent arrangement between said cage and said housing including a spring-pressed ball, means engageab-le by said ball at a position corresponding to the position of engagement by said relatively large roller with said dwell surface, whereby to indicate the position of maximum opening between the rollers to facilitate-the introduction of the stud therebetween and manual means including an arcuate slot in said housingand a radially extending handle protruding from said cage for manually adjusting the arcuate position of said cage with respect to said housing to either move the same to the position of maximum opening between the rollers or to effect the movement of said large roller into cooperation with said respective cam surfaces to reduce the space between said rollers and thus grip said stud.

2. A torque wrench for drivinglyengaging the curved surface of an elongated article, said wrench including, in combination, means defining a cylindrical housing having a coaxial bore therethrough, a cage and roller assembly coaxially journaled in said bore for arcuate movement therein and having one roller of a greater diameter than the remaining rollers, a recess formed in the bore of said housing opposite said one roller and defining a dwell surface and a cam surface on either side of said dwell surface, which cam surfaces cooperate with said one roller to move the same radially inwardly to effect gripping of said article between the rollers when said cage and roller assembly is adjusted arcuately with respect to the housing, the diameter'of said one roller being such that when said larger roller is in engagement with said dwell surface of said recess and said remaining rollers are in engagement with the bore of said housing, the axis of said housing and said assembly is substantially equidistant from the nearest surface of all of the rollers and the opening between said rollers is at its maximum.

3. A torque wrench for drivingly engaging the curved surface of an elongated article, said wrench including, in combination, means defining a cylindrical housing having a coaxial bore therethrough, a cage and roller assembly coaxially journaled in said bore for arcuate movement therein and having one roller of a greater diameter than the remaining rollers, an arcuate slot in said housing, a rod secured to said cage and protruding through the slot in said housing, a recess formed in the boreof said housing opposite said one roller and defining a dwell surface and a cam surface on either side of said dwell surface, which cam surfaces cooperate with said one roller to move the same radially inwardly to face of said recess and said remaining rollers are in engagement with the bore of said hous-t ing, the axis of said housing and said assembly is substantially equidistant from the nearest'surrollers.

face of all of the rollers and the opening between 10 said rollers is at its maximum, said position of maximum opening or variations therefrom :being visually indicated by said rod which additionally serves as means for manually adjusting the cage to said position of maximum opening or to a position causing gnipping of said article by said DELBERT S. OLIVER;

I JOHN KANUCH. 

